Positive displacement radical injection system

ABSTRACT

A system, comprising, a combustion chamber, and a free-radical injector configured to inject free radicals into the combustion chamber at an ignition timing to trigger combustion of a fuel-air mixture.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to and benefit of U.S. Non-Provisionalpatent application Ser. No. 12/944,675, entitled “Positive DisplacementRadical Injection System”, filed Nov. 11, 2010, which is hereinincorporated by reference in its entirety.

BACKGROUND

This section is intended to introduce the reader to various aspects ofart that may be related to various aspects of the present invention,which are described and/or claimed below. This discussion is believed tobe helpful in providing the reader with background information tofacilitate a better understanding of the various aspects of the presentinvention. Accordingly, it should be understood that these statementsare to be read in this light, and not as admissions of prior art.

Since its inception the internal combustion engine has become animportant part of everyday life. Internal combustion engines are nowused in a wide variety of situations ranging from motor vehicles tomachinery. To operate an internal combustion engine, fuel and air aremixed and ignited in a chemical reaction that turns chemical energy intouseful mechanical energy. This combustion process can create undesirablebyproducts such as carbon monoxide (CO), nitrogen oxides (NO_(x)), andnon-methane hydrocarbons (NMHC). These undesirable byproducts can becreated when the combustion process fails to burn all of the fuel in themixture and/or the combustion process takes too long allowing theseundesirable byproducts to form. As government agencies tightenrestrictions and corporations continue to promote their positiveenvironmental impact, a need exists to create more efficient enginesthat produce fewer undesirable emissions.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features, aspects, and advantages of the present invention willbecome better understood when the following detailed description is readwith reference to the accompanying figures in which like charactersrepresent like parts throughout the figures, wherein:

FIG. 1 is a schematic of an exemplary free radical injection system;

FIG. 2 is a flow chart of a process for free radical combustion in aninternal combustion engine according to one embodiment;

FIG. 3 is a graph illustrating the timing of the free radical injectionsystem with respect to the position of the piston according to oneembodiment;

FIG. 4 is a cross-sectional view of an embodiment two-stroke engine witha free radical injection device;

FIG. 5 is a cross-sectional view of an embodiment of a free radicalinjection device in the engine of FIG. 4;

FIG. 6 is a perspective view of an embodiment of a free radicalinjection device of FIG. 5;

FIG. 7 is a schematic of an embodiment of a free radical injectionsystem;

FIG. 8 is a schematic of an embodiment of a free radical injectionsystem;

FIG. 9 is a schematic of an embodiment of a free radical injectionsystem;

FIG. 10 is a schematic of an embodiment of a free radical injectionsystem;

FIG. 11 is a schematic of an embodiment of a free radical injectionsystem; and

FIGS. 12A and 12B are schematics of an embodiment of a free radicalinjection system, illustrating an engine cycle.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments of the present invention will bedescribed below. These described embodiments are only exemplary of thepresent invention. Additionally, in an effort to provide a concisedescription of these exemplary embodiments, all features of an actualimplementation may not be described in the specification. It should beappreciated that in the development of any such actual implementation,as in any engineering or design project, numerousimplementation-specific decisions must be made to achieve thedevelopers' specific goals, such as compliance with system-related andbusiness-related constraints, which may vary from one implementation toanother. Moreover, it should be appreciated that such a developmenteffort might be complex and time consuming, but would nevertheless be aroutine undertaking of design, fabrication, and manufacture for those ofordinary skill having the benefit of this disclosure.

As discussed below, the discussed embodiments provide a free radicalinjection system, which injects a free radicals into a combustionchamber to ignite a fuel-air mixture. The free radicals may be in eithera gaseous form or a liquid form. In certain embodiments, the freeradical injection may include one or more positive displacement devicesto inject the free radicals. For example, the positive displacement mayinclude a piston, a solenoid, a membrane, or other suitable mechanism.Alternatively, the free radical injection system may include apressurized source of free radicals, which are injected into thecombustion chamber via operation of a valve. The free radicals areinjected at an appropriate time to trigger ignition, and thus combustionin the combustion chamber.

FIG. 1 is a schematic of an embodiment of a system 10 having a freeradical injection system 12 coupled to a combustion chamber 14, whereinthe free radical injection system 12 is configured to inject freeradicals to trigger ignition in the combustion chamber 14. In certainembodiments, the free radicals may include gaseous peroxides, aldehydes,monatomic hydrogen, or any combination thereof. In other embodiments,the peroxides, aldehydes, monatomic hydrogen, or any combination thereofmay be combined with water to form liquid free radicals. As illustrated,the free radical injection system 12 includes a controller 19 coupled toa free radical intake or supply 16, a fuel intake or supply 18, and anair intake or supply 20. As discussed in detail below, the controller 19is configured to control the quantity and timing of free radicalinjection via the intake 16 in conjunction with the quantity and timingof fuel injection and air supply into the combustion chamber 14. Incertain embodiments, the free radical intake 16 includes a positivedisplacement device, such as a piston, a diaphragm, a solenoid, oranother suitable device. By further example, the positive displacementdevice may include rotary pumps, reciprocating pumps, gear pumps,progressing cavity pumps, peristaltic pumps. Some exemplary rotary pumpsmay include lobe, external gear, internal gear, screw, shuttle block,flexible vane or sliding vane, helical twisted roots, or liquid ringvacuum pumps. Some exemplary reciprocating pumps include piston anddiaphragm pumps. Regardless of the type of positive displacement device,the free radical intake 16 may positively force the free radicals intothe combustion chamber 14 to trigger ignition of a fuel air mixture fromthe fuel intake 18 and the air intake 20.

As illustrated, the combustion chamber 14 includes a piston 22 disposedin a cylinder 24, such as a piston-cylinder assembly of a combustionengine. For example, the combustion chamber 14 may be one of manycombustion chambers of a gasoline fueled engine or a diesel fueledengine. As the piston 22 moves upward within the cylinder 24, the piston22 compresses a combustion volume 26 having the air and eventually thefuel from the intakes 18 and 20. For example, the fuel intake 18 mayinject the fuel at one or more times during the upward stroke of thepiston 22 as the piston approaches a top dead center position. As thispoint, the fuel air mixture is at an elevated pressure and an elevatedtemperature due to the compression by the piston 22. At some time nearor after top dead center, the controller 19 is configured to inject thefree radicals from the free radical intake 16 into the combustion volume26 to ignite the fuel air mixture.

The combination of the fuel air mixture, the elevated pressure, theelevated temperature, and the free radicals enables the free radicals torapidly ignite the fuel air mixture. For example, the free radicalintake 16 may inject one or more streams or dispersed flows of the freeradicals into the combustion volume 26, thereby quickly igniting thefuel air mixture via free radical ignition (i.e., without a spark). Itshould be noted that the free radical induced ignition and combustion isparticularly more rapid than convention ignition mechanisms (e.g., sparkignition or compression ignition), and the rapid nature of the freeradical induced ignition and combustion may substantially reduce exhaustemissions.

FIG. 2 is a flow chart of an embodiment of a process 38 for free radicalinduced combustion in a combustion system. The process 38 includes anair intake into a combustion chamber (block 40), and a compression ofthe air in the combustion chamber (block 42). For example, thecombustion chamber 14 of FIG. 1 may compress the air via an upwardstroke of the piston 22 in the cylinder 24. At an appropriate timing,the process 38 intakes fuel into the combustion chamber (block 44) toenable fuel air mixing within the combustion chamber. For example, thefuel intake may occur during the upward stroke of the piston 22 prior toa top dead center position of the piston 22. At a subsequent timing, theprocess 38 may intake free radicals into the combustion chamber (block46). For example, the free radical intake may occur near, at, or afterthe top dead center position of the piston 22. Upon injection of thefree radicals, the process 38 rapidly triggers ignition of the fuel airmixture in the combustion chamber via the free radicals (block 48).While in the present embodiment fuel intake occurs prior to free radicalintake, other embodiments contemplate free radical intake before thefuel intake. In still further embodiments, fuel and free radical intakemay occur simultaneously.

In the process 38 of FIG. 2, the free radicals may be injected by apositive displacement device, an external source of pressurized freeradicals, or another suitable source. Again, the free radicals mayinclude peroxides, aldehydes, monatomic hydrogen, or any combinationthereof. In the presence of the elevated pressure and elevatedtemperature, the free radicals operate to rapidly ignite the fuel airmixture more uniformly and completely throughout the combustion chamber.The free radicals may be analogized with many small spark plugsdistributed throughout the combustion chamber, thereby providingmultiple distributed ignition points to improve the combustion process.Accordingly, it may be desirable to provide a uniform injection of thefree radicals throughout the combustion chamber. The free radicalsprovide more complete and uniform combustion, and in a much more rapidmanner. As a result, the free radical induced combustion may besubstantially more efficient with less undesirable exhaust emissions(e.g., less nitrogen oxides, or NO_(x)) as compared with conventionalignition systems. By using free radicals, rapid ignition and a lowercombustion temperature of the fuel/air mixture are possible. These twoconditions are unfavorable to NOx production. Furthermore, carbonmonoxide production is reduced, due to the more complete and uniformcombustion at a lower fuel/air ratio.

FIG. 3 is a graph of an embodiment of a timing scheme 50 for injectionof air, fuel, and free radicals with respect to the position of thepiston 22 in the combustion chamber 14 of FIG. 1. As illustrated, thetiming scheme 50 includes a piston timing curve 52, an air timing curve54, a fuel timing curve 56, a free radical timing curve 58, and acombustion timing curve 60. In general, the curves 54, 56, 58, and 60may occur in order as indicated by a time axis 62, but may temporallyoverlap with one another during a cycle of the piston 22 as indicated bya piston position axis 64. As illustrated by the piston timing curve 52,the piston 22 moves upward from a bottom dead center (BDC) position to atop dead center (TDC) position, and then back toward the BDC position.During this cycle of the piston 22, the combustion volume 26 compressesduring the upward compression stroke toward the TDC position, and thenexpands during the downward power stroke (or combustion) toward the BDCposition.

During the compression stroke, the timing scheme 50 may provide the airto the combustion chamber as indicated by the air timing curve 54, andthen subsequently provide the fuel to the combustion chamber asindicated by the fuel timing curve 56. In certain embodiments, the fueltiming curve 56 may include a single injection timing or multipleinjection timings, e.g., a pilot fuel injection and a main fuelinjection. At, near, or after the TDC position, the timing scheme 50 mayprovide the free radicals to the combustion chamber as indicated by thefree radical timing curve 58. In the illustrated embodiment the freeradical timing curve 58 occurs at least slightly after the TDC positionof the piston, at least in part due to the rapid ignition and combustioninduced by the free radicals. In some embodiments, the free radicals maybe injected between approximately 0 to 25, 0 to 20, 0 to 15, or 0 to 10degrees before or after the TDC position. For example, the free radicalsmay be injected at least approximately 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10degrees after the TDC position. In turn, the timing scheme 50 includesthe combustion timing curve 60, which substantially overlaps the freeradical timing curve 58. Again, the free radicals rapidly ignite thefuel air mixture in the combustion chamber, and thus the combustiontiming curve 60 is shown as starting at or slightly after the start ofthe free radical timing curve 58. While in the present embodiment thefree radicals are injected at or near TDC position it is understood thatfree radicals may be injected at BDC position or any position inbetween. Like free radical injection, fuel injection may also vary withrespect to the location of the piston. When and at what piston position,free radicals and fuel are injected into the cylinder depends on theparticular design.

FIG. 4 is a cross-sectional view of an embodiment of a two-stroke engine80 incorporating a free radical injection device 82 configured toprovide free radical induced ignition and combustion. In the illustratedembodiment, the engine 80 a fuel injector 84, a cylinder 86, a head 88,and a piston assembly 90. The illustrated cylinder 86 is generallyconcentric about a central axis 92 and includes an inner sidewall 94, anouter sidewall 96, an exhaust outlet 98, and an air inlet 100. The innersidewall 94 and the outer sidewall 96 are spaced away from each otherand together define a cavity 102 for circulating coolant around theinner sidewall 94 and cooling the engine 80. Coolant may flow into orout of the cavity 102 through an aperture 104 in the outer sidewall 96.The cavity 102 may also include a plurality of apertures 106 that placethe cavity 102 in fluid communication with portions of the head 88, asdescribed below. The inner sidewall 94 is penetrated by a plurality ofpassages 108 that converge in the air inlet 100 and a plurality ofpassages 110 that converge in the exhaust outlet 98. The passages 110may extend closer to the head 88 than the passages 108 to increase theportion of the piston's stroke during which exhaust gas may flow throughthe passages 110 relative to the portion of the piston's stroke duringwhich air may flow in through the passages 108. During a down stroke,exhaust gas may first flow out through the passages 110 before air flowsinto the cylinder 86 through the passages 108 and purges the remainingexhaust. In some embodiments, the cylinder 86 has a bore (diameter)between 10 and 20 inches, e.g., between 14 and 18 inches.

The cylinder 86 couples to the head 88, which also has a shape that isgenerally concentric about the central axis 92. In this embodiment, thehead 88 includes an inner wall 112, an outer wall 114, a cavity 116, acoolant inlet 118, a free radical injection device aperture 120, a gasinjection valve aperture 122, and bolts 124. One side of the inner wall112 defines a generally dome-shaped portion of a main combustion chamber126, and the space between the inner wall 112 and the outer wall 114generally defines the cavity 116.

In this embodiment, the cavity 116 is in fluid communication with thecoolant inlet 118 and with the coolant outlet 104 through both theapertures 106 and the cavity 102 in the cylinder 86. In someembodiments, the flow may be reversed and inlet 118 may be an outlet.The illustrated cavity 116 includes a plurality of passages 128 thatextend to the free radical injection device 82 for cooling the freeradical injection device 82. A portion of the cavity 116 also surroundsa part of the fuel injector 84.

The illustrated free radical injection device aperture 120 is generallycentrally located at the top of the head 88 and is generally concentricabout the central axis 92. As explained below, positioning the freeradical injection device 82 generally centrally above the maincombustion chamber 126 is believed to contribute to a more evenpropagation of a flame throughout the main combustion chamber 126 andimprove engine efficiency. In other embodiments, the free radicalinjection device 82 and the free radical injection device aperture 120may be located elsewhere on the head 88 or the engine 80, e.g., to theside of the central axis 92 similar to the gas injection valve 84. Thefree radical injection device aperture 120 extends between the maincombustion chamber 126 and the exterior of the head 88, and it includesa shoulder 130 and a sidewall 132 that abut seals on the free radicalinjection device 82, as described below. The shoulder 130 and thesidewall 132 may be generally concentric about the central axis 92.

The illustrated bolts 124 extend through the head 88 and thread to thecylinder 86, biasing the head 88 against the cylinder 86. A gasket 134may be positioned between the head 88 and the cylinder 86, such that itis compressed by the bolts 124. In this embodiment, the head 88 and thecylinder 86 include overlapping flanges 136 and 138. The illustratedflange 136 includes a fillet 140 on the side facing the main combustionchamber 126.

The piston assembly 90 includes a piston 142 and a shaft 144. In someembodiments, the piston 142 includes a crown 146 with a generallydome-shaped portion 148 and a chamfered portion 150, an aperture 152, aplurality of seals 154, and a sleeve 156. The illustrated pistonassembly 90 is generally concentric about the central axis 92. Thedome-shaped portion 148 of the crown 146 generally defines a segment ofa sphere, and the chamfer 150 generally defines a frustoconical volume.The piston 142 is illustrated at or near one end of its stroke, referredto as a bottom dead center. In this position, both the passages 108 andthe passages 110 are in fluid communication with the main combustionchamber 126. The aperture 152 includes internal threads that arecomplementary to external threads on a distal portion 158 of the shaft144. The illustrated piston assembly 90 includes three piston ring seals154 that are disposed above the sleeve 156 and below the chamfer 150.Other embodiments may include more or fewer seals 154 or other types ofseals. The sleeve 156 is a generally tubular member that is generallyconcentric about the central axis 92. The sleeve 156 extends a distancealong the cylinder 86 such that the sleeve 156 obstructs the passages108 and 110 when the piston assembly 90 is at the other end of itsstroke referred to as top dead center. In some embodiments, the sleeve90 may be longer than or generally equal to the length of the stroke ofthe piston assembly 90.

FIG. 5 is a cross-sectional view of an embodiment of the free radicalinjection device 82 of FIG. 4, illustrating a positive displacementinjection system 178 configured to positively force free radicals intothe combustion chamber 126 at an appropriate ignition timing. In theillustrated embodiment, the free radical injection device 82 includes anupper body 180, a lower body 182, a seal 184, a free radical source 186,and a controller 187. The positive displacement injection system 178includes a piston assembly 188, although any other suitable positivedisplacement device is within the scope of the disclosed embodiments. Inoperation, the controller 187 is configured to engage the pistonassembly 188 to positively displace free radicals from the free radicalsource 186 into the combustion chamber 126, thereby causing free radicalinduced ignition without a spark plug, glow plug, or the like. Forexample, the controller 187 may actuate the piston assembly 188 at anignition timing at, near, or slightly after top dead center (TDC) of thepiston stroke.

Turning now to structural features of the free radical injection device82, the upper body includes an outer surface 190, a pre-chamber 192, ashaft aperture 194, a free radical source aperture 196, a passage 198,and electromagnets 200. The outer surface 190 of the upper body 180includes a first flange 202, a recess 204, a seal 206 disposed in therecess 204, a chamfer 208, a shoulder 210, and a second flange 212. Theseal 206 may be an O-ring or other appropriate type of seal that sealscoolant within the cavity 116 of the head 88 (FIG. 4). The pre-chamber192 is generally cylindrical. The electromagnets 200 are secured withinthe pre-chamber 192 proximate the passage 198. The electromagnets 200maybe any electromagnets that change their north and south poles uponcommand by the controller 187. The free radical source aperture 196opens into the pre-chamber 192 allowing free radicals to enter from thefree radical source 186. The passage 198 defines a frustroconical topportion 214 and a narrow generally cylindrical bottom portion 216. Thefrustroconical top portion may assist in directing free radicals intothe narrow portion 216 of the passage 198. The passage 198 allows freeradicals entering the pre-chamber 192 to enter the lower body 182 of thefree radical injection device 82.

The illustrated lower body 182 includes an outer surface 230, a primarypassage 232, and secondary passages 234. The outer surface 230 furtherdefines an upper shoulder 236, a flange 238, a chamfer 240, a lowershoulder 242, a sidewall 244, and a dome 246. The flange 238 and uppershoulder 236 are configured to abut and overlap both the flange 212 andthe shoulder 210 of the upper body 180. In this embodiment, a weld 248joins the chamfer 240 on the lower body 182 to the chamfer 208 on theupper body 180. The illustrated upper body 180 and lower body 182 arecast and then machined separately before being joined permanently by theweld 248. In other embodiments, these components 180 and 182 may beseparable and joined with other features, e.g., a threaded connection orbolts. The lower shoulder 242 is generally perpendicular to the centralaxis 92 (FIG. 4) and abuts the seal 184. The sidewall 244 may define agenerally right circular-cylindrical volume and may be generallyconcentric about the central axis 92. The illustrated dome 246 generallydefines a segment of a sphere, e.g., a segment less than a hemisphere,but in other embodiments may have other shapes, such as a flat surface,a portion of an ellipsoid, or a faceted surface (which is not to suggestthat a faceted surface may not also generally define a segment of asphere or other curved shape).

The primary passage 232 may join the secondary passages 234 at an areathat generally lies along the central axis 92, and the secondarypassages 234 may be generally rotationally symmetric about the centralaxis 92. In this embodiment, the secondary passages 234 are at an anglewith respect to the central axis 92, which may be between approximately0 to 110 degrees, 10 to 80 degrees, or 10 to 30 degrees. In otherembodiments, the secondary passages 234 may extend in other directions,e.g., generally perpendicular to the central axis 92, radially outward.Both the primary passage 232 and the secondary passages 234 aregenerally straight, but in other embodiments, they may curve or bend.Both the primary passage 232 and the secondary passages 234 generallydefine right circular-cylindrical volumes, but in other embodiments,they may generally define other shapes, e.g., a non-rightcircular-cylindrical volume, an elliptical-cylindrical volume, arectangular cylindrical volume, a converging volume (e.g., conical), adiverging volume (e.g., conical), or some combination thereof.Additional details of the secondary passages 234 are described belowwith reference to FIG. 6.

The seal 184 is a generally annular member configured to seal the maincombustion chamber 126 from the cavity 116 in the head 88. In thisembodiment, the seal 184 is disposed around the walls 244 and againstthe shoulder 242.

Turning now to the positive displacement injection system 178, thepiston assembly 188 includes a shaft 218 and a piston 220 connected tothe shaft 218. As illustrated in FIG. 5 the piston 220 includes apermanent magnet, which interacts with the electromagnet 200 operated bythe controller 187 to provide reciprocal motion. During operation of thefree radical injection device 82, the free radicals are inserted intothe pre-chamber 192 of the upper body 180 between the permanent magnet220 and the electromagnet 200. Upon actuation by the controller 187, theelectromagnet 200 attracts the permanent magnet piston 220 towards theelectromagnets 200 in direction 222. The downward movement 222 of thepiston 220 forces (i.e., positively displaces) the free radicals throughthe passage 198, into the primary passage 232, and then out through thesecondary passages 234 into the combustion chamber 126. In order torepeatedly inject free radicals from the pre-chamber 192 into thecombustion chamber 126, the controller 187 then actuates theelectromagnet 200 to reverse the piston 220 to move in an oppositedirection 224 away from the electromagnets 200. Specifically, thecontroller 187 operates to reverse the polarity of the electromagnets200, such that a first polarity attracts the piston 220 in the downwarddirection 222 and a second polarity repels the piston 224 in theopposite upward direction 224. Upon completing the upward stroke of thepiston 220, the controller 187 then repeats the cycle by injectinganother volume of the free radicals into the pre-chamber 192, reversingthe polarity of the electromagnets 200 to cause downward movement 222 ofthe piston 220 to inject the free radicals, and then subsequentlyreversing the polarity of the electromagnets 200 to cause upwardmovement 224 of the piston 220 after the free radical injection. Inother embodiments, the piston 220 may include an electromagnet ratherthan a permanent magnet, and the electromagnet 200 may be exchanged fora permanent magnet. In still further embodiments, all of the magnets maybe electromagnets. Alternatively, the piston 220 may be driven byanother mechanism, such as a pneumatic drive.

FIG. 6 is a perspective view of an embodiment of the free radicalinjection device 82. As illustrated, in this embodiment, the features ofthe free radical injection device 82 are generally concentric about thecentral axis 92 except the flange 202. The flange 202 defines agenerally cuboid volume with chamfered corners. Apertures 270 may bedisposed in each of the corners for receiving bolts that secure the freeradical injection device 82 to the head 88. In this embodiment, the freeradical injection device 82 is secured to the head 88 without directlythreading the free radical injection device 82 to the head 88. Boltsextending through the apertures 270 bias the shoulder 242 against thehead 88 and restrict movement of the free radical injection device 82relative to the head 88.

As further illustrated in FIG. 6, the free radical injection device 82includes six secondary passages 234 to disperse the free radicals indifferent directions into the combustion chamber 126. In otherembodiments, the free radical injection device 82 may include more orfewer secondary passages 234, e.g. 1 to 50, 1 to 25, or 1 to 10secondary passages 234. For example, the free radical injection device82 may include at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 secondarypassages 234. As illustrated, the secondary passages 234 are generallyevenly distributed radially around the central axis 92 at approximately60 degree intervals. Other embodiments may include additional secondarypassages 234 that are at different angles with respect to the centralaxis 92, e.g., a secondary passage 234 that is generally coaxial withthe central axis 92 and another set of secondary passages 234 that areat a larger angle relative to the central axis 92 than the illustratedsecondary passages 234. In some embodiments, the secondary passages 234may exit the dome 246 at several different angles with respect to thecentral axis 92, e.g., ranging between approximately 0 to 90 degrees.For example, one or more secondary passages 234 may be disposed atangles of approximately 0, 15, 30, 45, 60, and 75 degrees relative tothe axis 92. Further, the passages 234 may have varying diameters orshapes. For instance, passages 234 at a larger angle relative to thecentral axis 92 may have a larger diameter than passages 234 at asmaller angle. While in the present embodiment, the dome definesmultiple passages 234, the dome may instead include a conical diffuserin lieu of multiple passages leading into the combustion chamber 126. Instill further embodiments, the dome may define a conical diffuser inassociation with a plurality of passages or perhaps even multipleconical diffusers for venting the free radicals in the combustionchamber. The conical diffuser may have an angle change betweenapproximately 5 to 20 degrees. Regardless, the passageways and diffuserswill vary in size, shape, and angles, depending on the size of thecombustion chamber 126, velocity suitable to effectively mix the freeradicals, and the desired ignition timing of the combustion process.

FIG. 7 is a schematic of an embodiment of a free radical injectiondevice 300 having a fluid-driven positive displacement system 301 todrive free radicals into a combustion chamber 322. As illustrated, thefree radical injection device 300 includes a pressurized fluid source302, free radical source 304, a cylinder 306, piston 308, springs 310,controller 312, and valve 314. The fluid-driven positive displacementsystem 301 generally includes the pressurized fluid source 302 incombination with the piston 308 and associated elements. The pressurizedfluid source 302 may include compressed air, exhaust gas, nitrogen,steam, hydraulic fluid, or any other suitable gas, liquid, or vapor. Asdiscussed above, the free radical source 304 may include peroxides,aldehydes, monatomic hydrogen, or any combination thereof.

During operation, free radicals are inserted into the cylinder 306 basedon signals received from the controller 312. When the free radicals areinside the cylinder 306, the controller 312 then actuates the valve 314.The valve 314 may be any suitable valve, such as a butterfly valve, agate valve, a pinch valve, or a ball valve. The controller 312 opens thevalve 314 releasing the pressurized fluid source through a passageway316 into the cylinder 306. The pressurized fluid contacts the piston308, thereby forcing the piston 308 to move in direction of arrow 318.As the piston 308 moves in the direction of arrow 318, the piston 308forces free radicals in the cylinder 306 to flow out of the cylinder 306through a passageway 320 and into a combustion chamber 322. Afterinjection of the free radicals into the combustion chamber 322, thepressurized fluid is removed and the valve 314 closed. Once the pressureis removed, the springs 310 retract the piston 308 in a directionopposite that of arrow 318. The process is repeated for each ignitionevent.

FIG. 8 is a schematic of an embodiment of a free radical injectiondevice 340 having a electronic-driven positive displacement system 341to drive free radicals into a combustion chamber 354. The free radicalinjection device 340 includes an electronic actuator 342, free radicalsource 344, a cylinder 346, piston 348, shaft 350, and controller 352.The electronic-driven positive displacement system 341 generallyincludes the electronic actuator 342 in combination with the piston 348and associated elements. The electronic actuator 342 may include asolenoid, an alternating current (AC) drive, a direct current (DC)drive, a piezoelectric drive, a linear motor, an induction motor, orsome combination thereof. As discussed above, the free radical source344 may include peroxides, aldehydes, monatomic hydrogen, or anycombination thereof.

During operation, free radicals are inserted into the cylinder 346 whensignaled by controller 352. When the free radicals are inside thecylinder 346, the controller 352 actuates the electronic actuator 342.The electronic actuator 342 then moves the piston 348 via the shaft 350in the direction of the combustion chamber 354. The movement of thepiston 348 forces the free radicals through a passageway 356 into thecombustion chamber 354, thereby causing free radical induced ignitionand combustion in the combustion chamber 354. After injection of thefree radicals into the combustion chamber 354, the electronic actuatorretracts the shaft 350 and piston 348. With the piston 348 retracted,free radicals may again be inserted into the cylinder 346 and theprocess is repeated.

FIG. 9 is a schematic of an embodiment of a free radical injectiondevice 370 having a fluid-driven positive displacement system 371 todrive free radicals into a combustion chamber 386. The free radicalinjection device 370 includes a pressurized fluid source 372, freeradical source 374, a cylinder 376, membrane 378, controller 380, andvalve 382. The fluid-driven positive displacement system 371 generallyincludes the pressurized fluid source 372 in combination with themembrane 378 and associated elements. The pressurized fluid source 372may include compressed air, exhaust gas, nitrogen, steam, hydraulicfluid, or any other suitable gas, liquid, or vapor. As discussed above,the free radical source 374 may include peroxides, aldehydes, monatomichydrogen, or any combination thereof.

During operation, free radicals are inserted into the cylinder 376 whensignaled by controller 380. When the free radicals are inside thecylinder 376, the controller 380 actuates the valve 382. The valve 382may be any suitable valve, such as a butterfly valve, a gate valve, apinch valve, or a ball valve. The controller 380 opens the valve 382releasing the pressurized fluid source through a passageway 384 into thecylinder 376. The pressurized fluid contacts the membrane 378 flexingthe membrane 378 in the direction of the combustion chamber 386. As themembrane 378 flexes in the direction of the combustion chamber 386, themembrane 378 forces free radicals in the cylinder 376 to flow outthrough a passageway 388 and into the combustion chamber 386. Afterinjection of the free radicals into the combustion chamber 386, thepressurized fluid is removed and the valve 382 is closed. Once thepressure is removed, the membrane 378 flexes back to a normal state. Theprocess is repeated for each ignition event.

FIG. 10 is a schematic of an embodiment of a free radical injectiondevice 400 having a pressurized free radical source 402. As illustrated,the free radical injection device 400 also includes a valve 404 and acontroller 406 configured to control flow of the pressurized freeradicals into a combustion chamber 408 at an appropriate ignitiontiming. In operation, the controller 406 actuates the valve 404 allowingthe pressurized free radicals to flow through a passageway 410 and intothe combustion chamber 408. Once a sufficient amount of free radicalshave passed through the passageway 410, the controller 406 closes thevalve 406 to terminate the flow of more pressurized free radicals. Theprocess is repeated for each ignition event. Again, the free radicalsare configured to rapidly ignite the fuel air mixture in the combustionchamber 408 without a spark, relying instead on the combination ofelevated pressure, elevated temperature, and distribution of freeradicals.

FIG. 11 is a schematic of an embodiment of a free radical injectiondevice 416 integrally driven by a combustion engine 418, therebyintegrally timing injection of free radicals with the engine cycle. Asillustrated, the combustion engine 418 includes a main engine crankshaft420 coupled to a main engine piston 422, wherein the crankshaft 420rotates to move the piston 422 reciprocally between a bottom dead center(BDC) position and a top dead center (TDC) position. In turn, thecrankshaft 420 is coupled to a primary gear 424 having teeth 426, whichengage teeth 428 of a secondary gear 430. In some embodiments, the gears424 and 430 may be connected via a timing chain or a timing belt. Thesecondary gear 430 is coupled to a secondary crankshaft 432, e.g., anignition timing crankshaft, which is coupled to a secondary piston 434that forces free radicals into a main combustion chamber 436. Thus, thecrankshafts 420 and 432 and associated gears 424 and 430 integrally timemovement of the pistons 422 and 434 to inject free radicals into thecombustion chamber 436 at a suitable ignition timing. In still otherembodiments, the pistons 434 and/or 422 may be cam-driven. Duringoperation, a controller 438 controls the injection of free radicals froma free radical source 440 into a cylinder 442 having the piston 434. Inturn, the piston 434 forces the free radicals into the combustionchamber 436 to cause free radical induced ignition and combustion of afuel air mixture. The combustion forces the piston 422 away from the TDCposition toward the BDC position, thereby causing rotation of thecrankshaft 420, gears 424, and 430, and crankshaft 432. Thus, during thedownward stroke of the piston 422, the various linkages cause an upwardstroke of the piston 434. The cycle repeats to cause free radicalinjection at, near, or slightly after the TDC position of the piston422. In the illustrated embodiment, the free radical injection device400 may be described as integrated to the combustion engine 402, andrelying on power of the engine 402 rather than an external power sourceto drive the free radical injection.

FIGS. 12A and 12B are schematics of an embodiment of a free radicalinjection device 470, illustrating an engine cycle. In particular, FIG.12A illustrates an upward stroke or compression stroke, whereas FIG. 12Billustrates a downward stroke or power stroke. As illustrated in FIGS.12A and 12B, the free radical injection device 470 includes a positivedisplacement device 472 and a controller 474 configured to controlinjection of free radicals for ignition of a fuel air mixture. Asillustrated in FIG. 12A, a fuel injector 476 injects a combustible fuel,such as a gaseous or liquid fuel, into a combustion chamber 478 during acompression stroke of a piston 480. During the compression stroke, thefuel mixes with air to create a fuel air mixture in the combustionchamber 478. Initially, the fuel air mixture may be ignited by a sparkplug or an external source of free radicals. However, combustion of thefuel air mixture creates unburned free radicals, which may be used as asource of free radical induced ignition in subsequent cycles of theengine. Again, the free radicals may include peroxides, aldehydes,monatomic hydrogen, or any combination thereof. In the illustratedembodiment, the free radicals from combustion may flow from thecombustion chamber toward the positive displacement device 472, asindicated by arrow 482. Subsequently, as illustrated in FIG. 12B, thepositive displacement device 472 may force those same free radicals(with or without an addition source of externally supplied freeradicals) back into the combustion chamber to provide free radicalinduced ignition, as indicated by arrow 484. For example, at anappropriate ignition timing, the controller 474 may actuate the positivedisplacement device 472 to provide a positive force against the freeradicals, thereby positively displacing the free radicals into thecombustion chamber. The positive displacement device 472 may includeelectrical, mechanical, or fluid driven actuators, as discussed above.The process repeats as each combustion event produces unburned freeradicals for use as an internal source of free radical induced ignitionin the next combustion event. The embodiment of FIGS. 12A and 12Breduces or eliminates the reliance on an external source of freeradicals, while also providing precise ignition timing using thepositive displacement device 472 in combination with the controller 474.

While the invention may be susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, it should be understood that the invention is not intended tobe limited to the particular forms disclosed. Rather, the invention isto cover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the followingappended claims.

The invention claimed is:
 1. A system, comprising: a combustion chamber;and a free-radical injector configured to receive free radicals externalfrom the free-radical injector and inject the free radicals into thecombustion chamber at an ignition timing to trigger combustion of afuel-air mixture.
 2. The system of claim 1, wherein the free-radicalinjector is configured to receive the free radicals from a combustionreaction in the combustion chamber.
 3. The system of claim 1, whereinthe free-radical injector is configured to receive the free radicalsfrom an external source separate from both the combustion chamber andthe free-radical injector.
 4. The system of claim 1, wherein thefree-radical injector comprises a positive displacement injectorconfigured to force the free radicals into the combustion chamber at anignition timing to trigger combustion of the fuel-air mixture.
 5. Thesystem of claim 4, wherein the positive displacement injector comprisesa rotary pump.
 6. The system of claim 4, wherein the positivedisplacement injector comprises a reciprocating pump.
 7. The system ofclaim 4, wherein the positive displacement injector comprises afluid-driven drive.
 8. The system of claim 4, wherein the positivedisplacement injector comprises an electronic drive.
 9. The system ofclaim 1, comprising a pre-chamber coupled to the combustion chamber,wherein the free-radical injector is configured to inject the freeradicals from the pre-chamber into the combustion chamber at theignition timing to trigger combustion of the fuel-air mixture.
 10. Thesystem of claim 1, wherein the free-radical injector excludes a sparkignition system.
 11. The system of claim 1, wherein the free radicalscomprise peroxides, aldehydes, or a combination thereof.
 12. A system,comprising: a free-radical ignition controller configured to control afree-radical injector to receive free radicals external from thefree-radical injector and inject the free radicals into a combustionchamber at an ignition timing to trigger combustion of a fuel-airmixture, wherein the free-radical injector is configured to receive thefree radicals from an external source separate from both the combustionchamber and the free-radical injector.
 13. The system of claim 12,wherein the free-radical ignition controller is configured to control apositive displacement pump to force a flow of the free radicals from thefree-radical injector into the combustion chamber.
 14. The system ofclaim 12, comprising the free-radical injector.
 15. The system of claim12, wherein the free-radical injector is configured to receive a portionof the free radicals from a combustion reaction in the combustionchamber.
 16. The system of claim 12, wherein the free radicals compriseperoxides, aldehydes, or a combination thereof.
 17. The system of claim12, comprising a combustion engine having the free-radical ignitioncontroller.
 18. A method, comprising: receiving free radicals into afree-radical injector from an external source separate from both acombustion chamber and the free-radical injector; and injecting the freeradicals from the free-radical injector into the combustion chamber totrigger combustion of a fuel-air mixture.
 19. The method of claim 18,wherein receiving the free radicals comprises receiving the freeradicals from a combustion reaction in the combustion chamber and theexternal source separate from.
 20. The method of claim 18, whereininjecting the free radicals comprises positively displacing the freeradicals to force a flow of the free radicals from the free-radicalinjector into the combustion chamber.